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Greg Gillen - One of the best experts on this subject based on the ideXlab platform.

  • Temperature-Controlled Depth Profiling of Poly(methyl methacrylate) Using Cluster Secondary Ion Mass Spectrometry. 1. InvestigatIon of Depth Profile Characteristics
    Analytical Chemistry, 2007
    Co-Authors: Christine M. Mahoney, And Albert J. Fahey, Greg Gillen
    Abstract:

    Secondary Ion mass spectrometry employing an SF5+ polyatomic primary Ion source was used to depth profile poly(methyl methacrylate) (PMMA) at a series of temperatures ranging from −75 °C to 125 °C, where the primary glass transitIon for PMMA occurs at 105 °C. The depth profile characteristics (e.g., interface widths, sputter rates, damage accumulatIon factors, normalized intensities, and overall Secondary Ion stability or constancy) were monitored as a functIon of temperature. It was found that, at low temperatures, the quality of the depth profiles improved considerably, having decreased damage accumulatIon, higher normalized intensities, and decreased interface widths, particularly at −75 °C. Higher temperatures were correlated with increased sputter rates. However, the improvements in interfacial widths and decreased damage accumulatIon were not as prevalent as observed at low temperatures. The importance of glass transitIon temperature (Tg) on the depth profile characteristics was also apparent. The r...

  • depth profiling of 4 acetamindophenol doped poly lactic acid films using cluster Secondary Ion mass spectrometry
    Analytical Chemistry, 2004
    Co-Authors: Christine M. Mahoney, Sonya Roberson, Greg Gillen
    Abstract:

    The feasibility of using cluster Secondary Ion mass spectrometry for depth profiling of drug delivery systems is explored. The behavior of various biodegradable polymer films under dynamic SF5+ pri...

  • depth profiling of 4 acetamindophenol doped poly lactic acid films using cluster Secondary Ion mass spectrometry
    Analytical Chemistry, 2004
    Co-Authors: Christine M. Mahoney, Sonya Roberson, Greg Gillen
    Abstract:

    The feasibility of using cluster Secondary Ion mass spectrometry for depth profiling of drug delivery systems is explored. The behavior of various biodegradable polymer films under dynamic SF5+ primary Ion bombardment was investigated, including several films doped with model drugs. The SF5+ depth profiles obtained from these biodegradable polymer films showed very little degradatIon in Secondary Ion signal as a functIon of increasing primary Ion dose, and it was discovered that the characteristic Ion signals for the polymers remained constant for Ion doses up to ∼5 × 1015 Ions/cm2. These results suggest that the polyester structure of the biodegradable polymers studied here allows for a greater ability to depth profile due to ease of main chain scissIon. Attempts were also made to depth profile through a series of poly(lactic acid) (PLA) films containing varying concentratIons of the drug 4-acetamidophenol. The depth profiles obtained from these films show very little decrease in both the 4-acetamidophen...

  • Secondary Ion mass spectrometry using cluster primary Ion beams
    Applied Surface Science, 2003
    Co-Authors: Greg Gillen, Albert J. Fahey
    Abstract:

    Abstract We have a developed a capability for conducting cluster Secondary Ion mass spectrometry (SIMS) experiments on commercially available SIMS instrumentatIon. This paper reviews our recent work on cluster Ion source development, elemental depth profiling with cluster primary Ion beams and the use of cluster Ion beams for organic surface characterizatIon. An area of particular interest is the observatIon that beam-induced damage for some organic materials is substantially reduced under cluster bombardment. This unique feature of cluster SIMS is utilized for molecular depth profiling of selected polymer films and for studying the spatial distributIon of high explosive particles by SIMS imaging. We also describe recent studies that may provide additIonal insight into possible mechanisms for the molecular Secondary Ion yield enhancement observed for organic thin films under cluster bombardment.

  • surface analysis studies of yield enhancements in Secondary Ion mass spectrometry by polyatomic projectiles
    Journal of Physical Chemistry B, 2001
    Co-Authors: Erick R. Fuoco, Greg Gillen, Muthu B. J. Wijesundara, William E Wallace, Luke Hanley
    Abstract:

    In this paper we examine the mechanism of Secondary Ion yield enhancements previously observed for polyatomic projectiles by measuring the weight loss, volume loss, and surface compositIon of poly(methyl methacrylate) (PMMA) films sputtered by keV SF5+ and Ar+ projectile Ions. The sputter yieldthe amount of material removed from the surface by 3.0 keV SF5+ projectileswas found to be 2.2 ± 0.8 higher than for Ar+ projectiles, measured by weight loss in the PMMA film with a quartz crystal microbalance. This result is consistent with sputter yield measurements reported here using 5.5 keV Ions and stylus profilometry. Thus, the >10× enhancement in Secondary Ion yield in Secondary Ion mass spectrometry observed for polyatomic Ion projectiles is not attributable to the modest ∼2× enhancements observed in the sputter yields for this molecular solid. Surface chemical measurements by X-ray photoelectron spectroscopy also indicated fundamental differences in atomic versus polyatomic sputtering mechanisms at 3.0 keV...

Jiro Matsuo - One of the best experts on this subject based on the ideXlab platform.

  • optimized alkali metal catIonizatIon in Secondary Ion mass spectrometry of polyethylene glycol oligomers with up to m z 10000 dependence on catIon species and concentratIon
    Analytical Chemistry, 2020
    Co-Authors: Toshio Seki, Takaaki Aoki, Hubert Gnaser, Jiro Matsuo
    Abstract:

    In Secondary Ion mass spectrometry (SIMS), the detectIon of large organic molecules is accomplished using cluster Ion bombardment. Ion formatIon often proceeds via catIonizatIon, through the attach...

  • effects of molecular weight and catIonizatIon agent on the sensitivity of bi cluster Secondary Ion mass spectrometry
    Rapid Communications in Mass Spectrometry, 2016
    Co-Authors: Makiko Fujii, Rie Shishido, Takaya Satoh, Shigeru Suzuki, Jiro Matsuo
    Abstract:

    RATIonALE Bi cluster Secondary Ion mass spectrometry (SIMS) is one of the most promising tools for precise analysis of synthetic polymers. However, the sensitivity in the high-mass regIon is still insufficient compared with matrix-assisted laser desorptIon/IonizatIon time-of-flight mass spectrometry (MALDI-TOFMS). Accordingly, the effects of metal assistance (catIonizatIon agents) were investigated in this study. METHODS To investigate the effects caused by varying the IonizatIon agent, three different polyethylene glycol (PEG) samples were prepared, one with an Ag-deposited film, and two others mixed with Ag and Na, respectively. The measurements were performed by using a commercial Bi cluster SIMS and MALDI-TOFMS systems. The mass spectrum obtained with MALDI-TOFMS was used as a reference molecular weight distributIon to evaluate the effects of molecular weight and primary Ion species (Bi+ , Bi3+ , Bi32+ ) on the sensitivity of Bi cluster SIMS. RESULTS The intensity of each Secondary Ion was the highest in Bi32+ irradiatIon, and the lowest in Bi+ irradiatIon. Regarding the catIonizatIon agents, the Secondary Ion yield was the highest for the sample mixed with Ag, while the degree of decay of sensitivity along with the increase in molecular weight was the smallest for the sample mixed with Na. CONCLUSIonS It was suggested that the catIonizatIon mechanism consists of pre-formed IonizatIon and gas-phase IonizatIon processes. The sensitivity of Bi cluster SIMS decreases to approximately one-fiftieth in every 1000 u. These results might help in understanding the mechanism of catIonizatIon and further enhancement of Secondary Ion yields of polymers. Copyright © 2016 John Wiley & Sons, Ltd.

  • precise and fast Secondary Ion mass spectrometry depth profiling of polymer materials with large ar cluster Ion beams
    Rapid Communications in Mass Spectrometry, 2009
    Co-Authors: Satoshi Ninomiya, Kazuya Ichiki, Yoshihiko Nakata, Hideaki Yamada, Takaaki Aoki, Toshio Seki, Jiro Matsuo
    Abstract:

    We demonstrate depth profiling of polymer materials by using large argon (Ar) cluster Ion beams. In general, depth profiling with Secondary Ion mass spectrometry (SIMS) presents serious problems in organic materials, because the primary keV atomic Ion beams often damage them and the molecular Ion yields decrease with increasing incident Ion fluence. Recently, we have found reduced damage of organic materials during sputtering with large gas cluster Ions, and reported on the unique Secondary Ion emissIon of organic materials. Secondary Ions from the polymer films were measured with a linear type time-of-flight (TOF) technique; the films were also etched with large Ar cluster Ion beams. The mean cluster size of the primary Ion beams was Ar700 and incident energy was 5.5 keV. Although the primary Ion fluence exceeded the static SIMS limit, the molecular Ion intensities from the polymer films remained constant, indicating that irradiatIon with large Ar cluster Ion beams rarely leads to damage accumulatIon on the surface of the films, and this characteristic is excellently suitable for SIMS depth profiling of organic materials. Copyright © 2009 John Wiley & Sons, Ltd.

  • precise and fast Secondary Ion mass spectrometry depth profiling of polymer materials with large ar cluster Ion beams
    Rapid Communications in Mass Spectrometry, 2009
    Co-Authors: Satoshi Ninomiya, Kazuya Ichiki, Yoshihiko Nakata, Hideaki Yamada, Takaaki Aoki, Toshio Seki, Jiro Matsuo
    Abstract:

    We demonstrate depth profiling of polymer materials by using large argon (Ar) cluster Ion beams. In general, depth profiling with Secondary Ion mass spectrometry (SIMS) presents serious problems in organic materials, because the primary keV atomic Ion beams often damage them and the molecular Ion yields decrease with increasing incident Ion fluence. Recently, we have found reduced damage of organic materials during sputtering with large gas cluster Ions, and reported on the unique Secondary Ion emissIon of organic materials. Secondary Ions from the polymer films were measured with a linear type time-of-flight (TOF) technique; the films were also etched with large Ar cluster Ion beams. The mean cluster size of the primary Ion beams was Ar 700 and incident energy was 5.5 keV. Although the primary Ion fluence exceeded the static SIMS limit, the molecular Ion intensities from the polymer films remained constant, indicating that irradiatIon with large Ar cluster Ion beams rarely leads to damage accumulatIon on the surface of the films, and this characteristic is excellently suitable for SIMS depth profiling of organic materials.

  • Secondary Ion emissIon from bio molecular thin films under Ion bombardment
    Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2007
    Co-Authors: Yoshihiko Nakata, Satoshi Ninomiya, Jiro Matsuo
    Abstract:

    Abstract We studied the Secondary Ion emissIon from arginine amino acid films bombarded with 500 keV Au Ions and compared the Secondary Ion intensities with those under 10 keV Ar Ion bombardment. A high sputtering yield of the protonated arginine Ions ( m / z 175) and a reductIon in Ion fragmentatIon were observed for 500 keV Au Ions. In additIon, the molecular Ion yield was compared to the yield measured with plasma desorptIon mass spectrometry (PDMS), and the data in this study did not show the tendency for the PDMS dependence. To the authors’ knowledge, this work is the first observatIon of the Secondary Ion emissIon for bio-molecular samples in the sub-MeV-energy range and the experimental results can give insights into the fundamental process of particle emissIon from bio-molecular samples.

Nicholas Winograd - One of the best experts on this subject based on the ideXlab platform.

  • Secondary Ion mass spectrometry images cardiolipins and phosphatidylethanolamines at the subcellular level
    Angewandte Chemie, 2019
    Co-Authors: Hua Tian, Paul Blenkinsopp, Louis J Sparvero, Andrew A Amoscato, Simon C Watkins, Hulya Bayir, Valerian E Kagan, Nicholas Winograd
    Abstract:

    MillIons of diverse molecules constituting the lipidome act as important signals within cells. Of these, cardiolipin (CL) and phosphatidylethanolamine (PE) participate in apoptosis and ferroptosis, respectively. Their subcellular distributIon is largely unknown. Imaging mass spectrometry is capable of deciphering the spatial distributIon of multiple lipids at subcellular levels. Here we report the development of a unique 70 keV gas-cluster Ion beam that consists of (CO2 )n + (n>10 000) projectiles. Coupled with direct current beam buncher-time-of-flight Secondary-Ion mass spectrometry, it is optimized for sensitivity towards high-mass species (up to m/z 3000) at high spatial resolutIon (1 μm). In combinatIon with immunohistochemistry, phospholipids, including PE and CL, have been assessed in subcellular compartments of mouse hippocampal neuronal cells and rat brain tissue.

  • gas cluster Ion beams for Secondary Ion mass spectrometry
    Reviews in Analytical Chemistry, 2018
    Co-Authors: Nicholas Winograd
    Abstract:

    Gas cluster Ion beams (GCIBs) provide new opportunities for bioimaging and molecular depth profiling with Secondary Ion mass spectrometry (SIMS). These beams, consisting of clusters containing thousands of particles, initiate desorptIon of target molecules with high yield and minimal fragmentatIon. This review emphasizes the unique opportunities for implementing these sources, especially for bioimaging applicatIons. Theoretical aspects of the cluster Ion/solid interactIon are developed to maximize conditIons for successful mass spectrometry. In additIon, the history of how GCIBs have become practical laboratory tools is reviewed. Special emphasis is placed on the versatility of these sources, as size, kinetic energy, and chemical compositIon can be varied easily to maximize lateral resolutIon, hopefully to less than 1 micron, and to maximize IonizatIon efficiency. Recent examples of bioimaging applicatIons are also presented.

  • IonizatIon probability in molecular Secondary Ion mass spectrometry protonatIon efficiency of sputtered guanine molecules studied by laser postIonizatIon
    Journal of Physical Chemistry C, 2017
    Co-Authors: Nicholas J Popczun, Lars Breuer, A Wucher, Nicholas Winograd
    Abstract:

    The prospect of improved Secondary Ion yields for Secondary Ion mass spectrometry (SIMS) experiments drives innovatIon of new primary Ion sources, instrumentatIon, and postIonizatIon techniques. An important factor affecting the detectIon sensitivity in molecular SIMS and other desorptIon techniques as well is believed to be the poor IonizatIon probability of a sputtered molecule, a value which is often assumed to be as low as 10–5 but at present is basically unknown. In order to estimate how much headroom there is for future developments toward strategies aimed at enhancing the IonizatIon probability, we study the protonatIon efficiency of sputtered guanine molecules for formatIon of [M + H]+ Secondary Ions using strong field laser postIonizatIon (LPI) to detect the corresponding neutral molecules. In order to allow a quantitative comparison of Secondary Ion and neutral yields, the postIonizatIon signal is corrected for undersampling of the principally detectable plume of sputtered neutral particles by t...

  • lipid imaging with time of flight Secondary Ion mass spectrometry tof sims
    Biochimica et Biophysica Acta, 2011
    Co-Authors: Melissa K Passarelli, Nicholas Winograd
    Abstract:

    Fundamental advances in Secondary Ion mass spectrometry (SIMS) now allow for the examinatIon and characterizatIon of lipids directly from biological materials. The successful applicatIon of SIMS-based imaging in the investigatIon of lipids directly from tissue and cells are demonstrated. Common complicatIons and technical pitfalls are discussed. In this review, we examine the use of cluster Ion sources and cryogenically compatible sample handling for improved Ion yields and to expand the applicatIon potential of SIMS. Methodological improvements, including pre-treating the sample to improve Ion yields and protocol development for 3-dimensIonal analyses (i.e. molecular depth profiling), are also included in this discussIon. New high performance SIMS instruments showcasing the most advanced instrumental developments, including tandem MS capabilities and continuous Ion beam compatibility, are described and the future directIon for SIMS in lipid imaging is evaluated.

  • Secondary Ion ms imaging of lipids in picoliter vials with a buckminsterfullerene Ion source
    Analytical Chemistry, 2005
    Co-Authors: Sara G Ostrowski, Christopher Szakal, Joseph Kozole, Thomas P Roddy, And Andrew G Ewing, Nicholas Winograd
    Abstract:

    InvestigatIon of the spatial distributIon of lipids in cell membranes can lead to an improved understanding of the role of lipids in biological functIon and disease. Time-of-flight Secondary Ion mass spectrometry is capable of molecule-specific imaging of biological molecules across single cells and has demonstrated potential for examining the functIonal segregatIon of lipids in cell membranes. In this paper, standard SIMS spectra are analyzed for phosphatidylethanolamine, phosphatidylglycerol, phosphatidylserine, phosphatidylinositol, cholesterol, and sulfatide. Importantly, each of the lipids result in signature mass spectral peaks that allow them to be identified. These signature peaks are also useful for imaging experiments and are utilized here to simultaneously image lipids on a micrometer scale in picoliter vials. Because the low Secondary Ion signal achieved for lipids from an atomic primary Ion source makes cell-imaging experiments challenging, improving signal with cluster primary Ion sources is...

Christine M. Mahoney - One of the best experts on this subject based on the ideXlab platform.

  • cluster Secondary Ion mass spectrometry of polymers and related materials
    Mass Spectrometry Reviews, 2010
    Co-Authors: Christine M. Mahoney
    Abstract:

    Cluster Secondary Ion mass spectrometry (cluster SIMS) has played a critical role in the characterizatIon of polymeric materials over the last decade, allowing for the ability to obtain spatially resolved surface and in-depth molecular informatIon from many polymer systems. With the advent of new molecular sources such as , , , and , there are considerable increases in Secondary Ion signal as compared to more conventIonal atomic beams (Ar+, Cs+, or Ga+). In additIon, compositIonal depth profiling in organic and polymeric systems is now feasible, without the rapid signal decay that is typically observed under atomic bombardment. The premise behind the success of cluster SIMS is that compared to atomic beams, polyatomic beams tend to cause surface-localized damage with rapid sputter removal rates, resulting in a system at equilibrium, where the damage created is rapidly removed before it can accumulate. Though this may be partly true, there are actually much more complex chemistries occurring under polyatomic bombardment of organic and polymeric materials, which need to be considered and discussed to better understand and define the important parameters for successful depth profiling. The following presents a review of the current literature on polymer analysis using cluster beams. This review will focus on the surface and in-depth characterizatIon of polymer samples with cluster sources, but will also discuss the characterizatIon of other relevant organic materials, and basic polymer radiatIon chemistry. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:247–293, 2010

  • Temperature-Controlled Depth Profiling of Poly(methyl methacrylate) Using Cluster Secondary Ion Mass Spectrometry. 1. InvestigatIon of Depth Profile Characteristics
    Analytical Chemistry, 2007
    Co-Authors: Christine M. Mahoney, And Albert J. Fahey, Greg Gillen
    Abstract:

    Secondary Ion mass spectrometry employing an SF5+ polyatomic primary Ion source was used to depth profile poly(methyl methacrylate) (PMMA) at a series of temperatures ranging from −75 °C to 125 °C, where the primary glass transitIon for PMMA occurs at 105 °C. The depth profile characteristics (e.g., interface widths, sputter rates, damage accumulatIon factors, normalized intensities, and overall Secondary Ion stability or constancy) were monitored as a functIon of temperature. It was found that, at low temperatures, the quality of the depth profiles improved considerably, having decreased damage accumulatIon, higher normalized intensities, and decreased interface widths, particularly at −75 °C. Higher temperatures were correlated with increased sputter rates. However, the improvements in interfacial widths and decreased damage accumulatIon were not as prevalent as observed at low temperatures. The importance of glass transitIon temperature (Tg) on the depth profile characteristics was also apparent. The r...

  • depth profiling of 4 acetamindophenol doped poly lactic acid films using cluster Secondary Ion mass spectrometry
    Analytical Chemistry, 2004
    Co-Authors: Christine M. Mahoney, Sonya Roberson, Greg Gillen
    Abstract:

    The feasibility of using cluster Secondary Ion mass spectrometry for depth profiling of drug delivery systems is explored. The behavior of various biodegradable polymer films under dynamic SF5+ pri...

  • depth profiling of 4 acetamindophenol doped poly lactic acid films using cluster Secondary Ion mass spectrometry
    Analytical Chemistry, 2004
    Co-Authors: Christine M. Mahoney, Sonya Roberson, Greg Gillen
    Abstract:

    The feasibility of using cluster Secondary Ion mass spectrometry for depth profiling of drug delivery systems is explored. The behavior of various biodegradable polymer films under dynamic SF5+ primary Ion bombardment was investigated, including several films doped with model drugs. The SF5+ depth profiles obtained from these biodegradable polymer films showed very little degradatIon in Secondary Ion signal as a functIon of increasing primary Ion dose, and it was discovered that the characteristic Ion signals for the polymers remained constant for Ion doses up to ∼5 × 1015 Ions/cm2. These results suggest that the polyester structure of the biodegradable polymers studied here allows for a greater ability to depth profile due to ease of main chain scissIon. Attempts were also made to depth profile through a series of poly(lactic acid) (PLA) films containing varying concentratIons of the drug 4-acetamidophenol. The depth profiles obtained from these films show very little decrease in both the 4-acetamidophen...

Olivier Laprévote - One of the best experts on this subject based on the ideXlab platform.

  • Lipid imaging with cluster time-of-flight Secondary Ion mass spectrometry
    Analytical and Bioanalytical Chemistry, 2008
    Co-Authors: Alain Brunelle, Olivier Laprévote
    Abstract:

    This brief article provides an overview of the current state of the art in biological imaging mass spectrometry using cluster time-of-flight Secondary Ion mass spectrometry (TOF–SIMS). Recent and spectacular improvements in terms of sensitivity of TOF–SIMS imaging methods have allowed many biological applicatIons to recently be successfully tested, such as mapping of lipid disorders in human muscles of a patient suffering from dystrophy, localizatIon of surfactins after the swarming of bacteria on a surface, or lipid mapping over whole-body animal sectIons.

  • lipid mapping in human dystrophic muscle by cluster time of flight Secondary Ion mass spectrometry imaging
    Journal of Lipid Research, 2008
    Co-Authors: Nora Tahallah, Alain Brunelle, Sabine De La Porte, Olivier Laprévote
    Abstract:

    Human striated muscle samples, from male control and Duchenne Muscular Dystrophy (DMD)-affected children, have been subjected to cluster-time-of-flight Secondary Ion mass spectrometry (cluster-ToF-SIMS) imaging, using a 25 keV Bi3+ liquid metal Ion gun, under static SIMS conditIons. Spectra and Ion density maps, or Secondary Ion images, have been acquired in both positive and negative Ion mode over several areas of 500 × 500 μm2 (image resolutIon 256 × 256 pixels). Characteristic distributIons of various lipids have been observed. Vitamin E and phosphatidylinositols have been found to concentrate within the cells, whereas intact phosphocholines accumulated over the most damaged areas of the dystrophic muscles, together with cholesterol and sphingomyelin species. Fatty acyl chains compositIon varied depending on the regIon, allowing estimatIon of the local damage extent.

  • biological tissue imaging with time of flight Secondary Ion mass spectrometry and cluster Ion sources
    Journal of Mass Spectrometry, 2005
    Co-Authors: Alain Brunelle, David Touboul, Olivier Laprévote
    Abstract:

    Time-of-flight Secondary Ion mass spectrometry (TOF-SIMS) using liquid metal Ion guns (LMIGs) is now sensitive enough to produce molecular-Ion images directly from biological tissue samples. Primary cluster Ions strike a spot on the sample to produce a mass spectrum. An image of this sample is achieved by rastering the irradiated point over the sample surface. The use of Secondary Ion mass spectrometry for mapping biological tissue surfaces provides unique analytical capabilities; in particular, it enables in a single acquisitIon a large variety of biological compounds to be localised on a micrometer scale and scrutinised for colocalisatIons. Without any treatment of the sample, this method is fully compatible with subsequent and complementary analyses like fluorescence microscopy, histochemical staining, or even matrix-assisted laser desorptIon/IonisatIon imaging. Basic physical concepts, required instrumentatIon (Ion source and mass analyzer), sample preparatIon methods, image acquisitIon, image processing, and emerging biological applicatIons will be described and discussed. Copyright © 2005 John Wiley & Sons, Ltd.

  • biological tissue imaging with time of flight Secondary Ion mass spectrometry and cluster Ion sources
    Journal of Mass Spectrometry, 2005
    Co-Authors: Alain Brunelle, David Touboul, Olivier Laprévote
    Abstract:

    Time-of-flight Secondary Ion mass spectrometry (TOF-SIMS) using liquid metal Ion guns (LMIGs) is now sensitive enough to produce molecular-Ion images directly from biological tissue samples. Primary cluster Ions strike a spot on the sample to produce a mass spectrum. An image of this sample is achieved by rastering the irradiated point over the sample surface. The use of Secondary Ion mass spectrometry for mapping biological tissue surfaces provides unique analytical capabilities; in particular, it enables in a single acquisitIon a large variety of biological compounds to be localised on a micrometer scale and scrutinised for colocalisatIons. Without any treatment of the sample, this method is fully compatible with subsequent and complementary analyses like fluorescence microscopy, histochemical staining, or even matrix-assisted laser desorptIon/IonisatIon imaging. Basic physical concepts, required instrumentatIon (Ion source and mass analyzer), sample preparatIon methods, image acquisitIon, image processing, and emerging biological applicatIons will be described and discussed.